BaselineA baseline study of coastal water quality in the Lembeh Strait of North Sulawesi, Indonesia, in 2013

- The spatial distribution of nutrient concentration and mol ratios in the Lembeh Strait was studied.
- P was found to be the limiting factor in phytoplankton growth compared to N and Si in general.
- The eutrophication status of the strait was level 1 (poor nutrition).

The concentrations of nutrients (NO2-N, NO3-N, NH4-N, PO4-P, and SiO3-Si) and their ratios in the Lembeh Strait were estimated in April 2013, off the northeastern coast of Sulawesi in Indonesia. The concentrations of dissolved inorganic nitrogen (DIN) (NO2-N + NO3-N + NH4-N) and PO4-P were low, with a maximum of 0.181 and 0.007 mg/L, respectively. P was found to be the limiting factor controlling phytoplankton growth overall. According to a potential eutrophication assessment model, both the surface water and the water at a depth of 15 m were classified as water 1 (poor nutrition). This study provides baseline information including chemical datasets for future pollution monitoring and management programs in this area.